/*
   There are a total of 8 entries in the algebraic variable array.
   There are a total of 4 entries in each of the rate and state variable arrays.
   There are a total of 17 entries in the constant variable array.
 */
/*
 * VOI is time in component environment (minute).
 * CONSTANTS[0] is AMK in component electrolytes (dimensionless).
 * CONSTANTS[1] is TVD in component electrolytes (L_per_minute).
 * CONSTANTS[2] is NOD in component electrolytes (monovalent_mEq_per_minute).
 * CONSTANTS[3] is STH in component electrolytes (dimensionless).
 * CONSTANTS[4] is KOD in component electrolytes (monovalent_mEq_per_minute).
 * CONSTANTS[5] is VUD in component electrolytes (L_per_minute).
 * ALGEBRAIC[3] is VEC in component extracellular_fluid_volume (litre).
 * ALGEBRAIC[4] is CNA in component extracellular_Na_concentration (monovalent_mEq_per_litre).
 * CONSTANTS[6] is NID in component parameter_values (monovalent_mEq_per_minute).
 * CONSTANTS[7] is TRPL in component parameter_values (L_per_minute).
 * CONSTANTS[11] is NED in component extracellular_Na_concentration (monovalent_mEq_per_minute).
 * STATES[0] is NAE in component extracellular_Na_concentration (monovalent_mEq).
 * CONSTANTS[12] is AMK1 in component aldosterone_effect_on_cellular_K_distribution (dimensionless).
 * CONSTANTS[8] is ALCLK in component parameter_values (dimensionless).
 * ALGEBRAIC[5] is CKE in component extracellular_K_concentration (monovalent_mEq_per_litre).
 * ALGEBRAIC[0] is KE in component extracellular_K_concentration (monovalent_mEq).
 * STATES[1] is KTOT in component extracellular_K_concentration (monovalent_mEq).
 * CONSTANTS[9] is KID in component parameter_values (monovalent_mEq_per_minute).
 * CONSTANTS[13] is KTOTD in component extracellular_K_concentration (monovalent_mEq_per_minute).
 * STATES[2] is VIC in component intracellular_fluid_volume (litre).
 * ALGEBRAIC[2] is CKI in component intracellular_K_concentration (monovalent_mEq_per_litre).
 * ALGEBRAIC[1] is KI in component intracellular_K_concentration (monovalent_mEq).
 * ALGEBRAIC[7] is VID in component intracellular_fluid_volume (L_per_minute).
 * CONSTANTS[10] is VIDML in component parameter_values (litre2_per_monovalent_mEq_per_minute).
 * ALGEBRAIC[6] is CCD in component intracellular_fluid_volume (monovalent_mEq_per_litre).
 * STATES[3] is VTW in component total_body_water (litre).
 * RATES[0] is d/dt NAE in component extracellular_Na_concentration (monovalent_mEq).
 * RATES[1] is d/dt KTOT in component extracellular_K_concentration (monovalent_mEq).
 * RATES[2] is d/dt VIC in component intracellular_fluid_volume (litre).
 * RATES[3] is d/dt VTW in component total_body_water (litre).
 */
void
initConsts(double* CONSTANTS, double* RATES, double *STATES)
{
CONSTANTS[0] = 1.037;
CONSTANTS[1] = 0.000980838;
CONSTANTS[2] = 0.0959449;
CONSTANTS[3] = 0.977181;
CONSTANTS[4] = 0.0804374;
CONSTANTS[5] = 0.000989;
CONSTANTS[6] = 0.1;
CONSTANTS[7] = 0;
STATES[0] = 2109.91;
CONSTANTS[8] = 0.3;
STATES[1] = 3622.54;
CONSTANTS[9] = 0.08;
STATES[2] = 25.0404;
CONSTANTS[10] = 0.01;
STATES[3] = 39.8952;
CONSTANTS[11] = ( CONSTANTS[6]*CONSTANTS[3] - CONSTANTS[2])+ CONSTANTS[7]*142.000;
CONSTANTS[12] =  (CONSTANTS[0] - 1.00000)*CONSTANTS[8]+1.00000;
CONSTANTS[13] = CONSTANTS[9] - CONSTANTS[4];
CONSTANTS[14] = CONSTANTS[1] - CONSTANTS[5];
CONSTANTS[15] = CONSTANTS[11];
CONSTANTS[16] = CONSTANTS[13];
}
void
computeRates(double VOI, double* CONSTANTS, double* RATES, double* STATES, double* ALGEBRAIC)
{
RATES[3] = CONSTANTS[14];
RATES[0] = CONSTANTS[15];
RATES[1] = CONSTANTS[16];
ALGEBRAIC[3] = STATES[3] - STATES[2];
ALGEBRAIC[4] = STATES[0]/ALGEBRAIC[3];
ALGEBRAIC[0] = (STATES[1] - 3000.00)/( CONSTANTS[12]*9.33330);
ALGEBRAIC[1] = STATES[1] - ALGEBRAIC[0];
ALGEBRAIC[2] = ALGEBRAIC[1]/STATES[2];
ALGEBRAIC[6] = ALGEBRAIC[2] - ALGEBRAIC[4];
ALGEBRAIC[7] =  ALGEBRAIC[6]*CONSTANTS[10];
RATES[2] = ALGEBRAIC[7];
}
void
computeVariables(double VOI, double* CONSTANTS, double* RATES, double* STATES, double* ALGEBRAIC)
{
ALGEBRAIC[3] = STATES[3] - STATES[2];
ALGEBRAIC[4] = STATES[0]/ALGEBRAIC[3];
ALGEBRAIC[0] = (STATES[1] - 3000.00)/( CONSTANTS[12]*9.33330);
ALGEBRAIC[1] = STATES[1] - ALGEBRAIC[0];
ALGEBRAIC[2] = ALGEBRAIC[1]/STATES[2];
ALGEBRAIC[6] = ALGEBRAIC[2] - ALGEBRAIC[4];
ALGEBRAIC[7] =  ALGEBRAIC[6]*CONSTANTS[10];
ALGEBRAIC[5] = ALGEBRAIC[0]/ALGEBRAIC[3];
}